It is known to store biological samples in cryogenic liquids such as liquid nitrogen due to the cryogenic conditions that preserve the integrity of the biological samples. In liquid nitrogen storage, samples are received in any appropriate container and immersed in a bath of liquid nitrogen stored in a tank.
Due to the cold temperature, the tanks are typically made of robust insulating material. Accordingly, for the various samples to be identified, it may be required to open the tank, to remove racks supporting cryo boxes or canisters containing vials from the tank. However, the opening of the tank, and the handling of the samples in and out of the tank expose the samples to a warmer temperature and cause evaporation of liquid nitrogen among other things. It is known to keep a list of samples per tank, with the occasional surveying of the samples by the opening of the storage tank, and with the possible removal from the storage tank, but this requires that the list be updated for every movement of samples. In parallel, technologies that could assist in automating the identification, such as wireless identification technologies, have not been used in liquid nitrogen storage due to the incapacity of such wireless identification systems to communicate with wireless tags through the tank walls, and/or through the liquid phase of nitrogen, or like liquefied cryogenic refrigerants.